A typical vane-type camshaft phaser for changing the phase relationship between a crankshaft and a camshaft of an internal combustion engine generally comprises a plurality of outwardly-extending vanes on a rotor interspersed with a plurality of inwardly-extending lobes on a stator, forming alternating advance and retard chambers between the vanes and lobes. Engine oil is selectively supplied to either the advance chambers or the retard chambers and vented from the other of the advance and retard chambers in order to rotate the rotor within the stator and thereby change the phase relationship between the camshaft and the crankshaft. Some camshaft phasers include a valve spool within the camshaft phaser in order to selectively supply and vent oil to and from the advance and retard chambers as necessary in order to achieve the desired phase relationship between the camshaft and the crankshaft. When the oil is vented from either the advance chambers or the retard chambers, the oil is typically drained out of the camshaft phaser and allowed to reach a drive member, such as a chain, gear, or belt, which transfers rotational motion from the crankshaft to the camshaft phaser. While this may be acceptable to some drive members, particularly chains and gears, other drive members, particularly belts, may not tolerate exposure to oil.
United States Patent Application Publication No. US 2014/0150742 A1 to Kinouchi teaches a camshaft phaser having a first tubular portion extending from a housing of the camshaft phaser and a second tubular portion that extends from a solenoid of the camshaft phaser. The first tubular portion cooperates with the second tubular portion to form an oil accumulating chamber which captures oil that is vented from the camshaft phaser, thereby preventing oil from reaching the drive belt. However, the solenoid actuator is attached to an engine cover which encloses the drive belt. Consequently, in order to remove the engine cover to replace or service the drive belt, the solenoid must be separated from the camshaft phaser, and oil that has accumulated in the oil accumulating chamber is allowed to escape and contaminate the area occupied by the drive belt. As a result, the oil that has escaped must be cleaned up before reassembling the engine cover.
What is needed is a camshaft phaser which minimizes or eliminates one or more the shortcomings as set forth above.